The finding that patients with NSCLC show higher levels of IL-22 in pulmonary lavage specimens is in line with the results of a previous study reporting that lung cancer cells may produce IL-22 [11]: Zhang and colleagues found high expression of IL-22 in primary tumour tissue, serum, and malignant pleural effusion of NSCLC patients, as well as expression of the IL-22 receptor (IL-22-R1) on lung cancer cell lines. Here, IL22 is linked to lung carcinoma.